/*

 * HEIF codec.

 * Copyright (c) 2017 Dirk Farin <dirk.farin@gmail.com>

 *

 * This file is part of libheif.

 *

 * libheif is free software: you can redistribute it and/or modify

 * it under the terms of the GNU Lesser General Public License as

 * published by the Free Software Foundation, either version 3 of

 * the License, or (at your option) any later version.

 *

 * libheif is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License

 * along with libheif.  If not, see <http://www.gnu.org/licenses/>.

 */

#include "hevc.h"

#include "codecs/hevc_boxes.h"

#include "bitstream.h"

#include "error.h"

#include "file.h"

#include "codecs/hevc_dec.h"

#include <cassert>

#include <cmath>

#include <cstring>

#include <iomanip>

#include <string>

#include <utility>

#include "api_structs.h"

#include "codecs/hevc_enc.h"

ImageItem_HEVC::ImageItem_HEVC(HeifContext* ctx, heif_item_id id)

    : ImageItem(ctx, id)

{

  m_encoder = std::make_shared<Encoder_HEVC>();

}

ImageItem_HEVC::ImageItem_HEVC(HeifContext* ctx)

    : ImageItem(ctx)

{

  m_encoder = std::make_shared<Encoder_HEVC>();

}

Error ImageItem_HEVC::initialize_decoder()

{

  auto hvcC_box = get_property<Box_hvcC>();

  if (!hvcC_box) {

    return Error{heif_error_Invalid_input,

                 heif_suberror_No_hvcC_box};

  }

  m_decoder = std::make_shared<Decoder_HEVC>(hvcC_box);

  return Error::Ok;

}

void ImageItem_HEVC::set_decoder_input_data()

{

  DataExtent extent;

  extent.set_from_image_item(get_context()->get_heif_file(), get_id());

  m_decoder->set_data_extent(std::move(extent));

}

heif_brand2 ImageItem_HEVC::get_compatible_brand() const

{

  auto hvcC = get_property<Box_hvcC>();

  if (has_essential_property_other_than(std::set{fourcc("hvcC"),

                                                 fourcc("irot"),

                                                 fourcc("imir"),

                                                 fourcc("clap")})) {

    return 0;

  }

  const auto& config = hvcC->get_configuration();

  if (config.is_profile_compatibile(HEVCDecoderConfigurationRecord::Profile_Main) ||

      config.is_profile_compatibile(HEVCDecoderConfigurationRecord::Profile_MainStillPicture)) {

    return heif_brand2_heic;

  }

  if (config.is_profile_compatibile(HEVCDecoderConfigurationRecord::Profile_Main10) ||

      config.is_profile_compatibile(HEVCDecoderConfigurationRecord::Profile_RExt)) {

    return heif_brand2_heix;

  }

  // TODO: what brand should we use for this case?

  return heif_brand2_heix;

}

Result<std::vector<uint8_t>> ImageItem_HEVC::read_bitstream_configuration_data() const

{

  return m_decoder->read_bitstream_configuration_data();

}

Result<std::shared_ptr<class Decoder>> ImageItem_HEVC::get_decoder() const

{

  return {m_decoder};

}

std::shared_ptr<class Encoder> ImageItem_HEVC::get_encoder() const

{

  return m_encoder;

}

void ImageItem_HEVC::set_preencoded_hevc_image(const std::vector<uint8_t>& data)

{

  auto hvcC = std::make_shared<Box_hvcC>();

  // --- parse the h265 stream and set hvcC headers and compressed image data

  int state = 0;

  bool first = true;

  bool eof = false;

  int prev_start_code_start = -1; // init to an invalid value, will always be overwritten before use

  int start_code_start;

  int ptr = 0;

  for (;;) {

    bool dump_nal = false;

    uint8_t c = data[ptr++];

    if (state == 3) {

      state = 0;

    }

    if (c == 0 && state <= 1) {

      state++;

    }

    else if (c == 0) {

      // NOP

    }

    else if (c == 1 && state == 2) {

      start_code_start = ptr - 3;

      dump_nal = true;

      state = 3;

    }

    else {

      state = 0;

    }

    if (ptr == (int) data.size()) {

      start_code_start = (int) data.size();

      dump_nal = true;

      eof = true;

    }

    if (dump_nal) {

      if (first) {

        first = false;

      }

      else {

        std::vector<uint8_t> nal_data;

        size_t length = start_code_start - (prev_start_code_start + 3);

        nal_data.resize(length);

        assert(prev_start_code_start >= 0);

        memcpy(nal_data.data(), data.data() + prev_start_code_start + 3, length);

        int nal_type = (nal_data[0] >> 1);

        switch (nal_type) {

          case 0x20:

          case 0x21:

          case 0x22:

            hvcC->append_nal_data(nal_data);

            break;

          default: {

            std::vector<uint8_t> nal_data_with_size;

            nal_data_with_size.resize(nal_data.size() + 4);

            memcpy(nal_data_with_size.data() + 4, nal_data.data(), nal_data.size());

            nal_data_with_size[0] = ((nal_data.size() >> 24) & 0xFF);

            nal_data_with_size[1] = ((nal_data.size() >> 16) & 0xFF);

            nal_data_with_size[2] = ((nal_data.size() >> 8) & 0xFF);

            nal_data_with_size[3] = ((nal_data.size() >> 0) & 0xFF);

            get_file()->append_iloc_data(get_id(), nal_data_with_size, 0);

          }

            break;

        }

      }

      prev_start_code_start = start_code_start;

    }

    if (eof) {

      break;

    }

  }

  get_file()->add_property(get_id(), hvcC, true);

}